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Question
Write scientific reasons.
The value of gravitational acceleration (g) decreases as we go deep inside the earth.
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Solution
- The acceleration due to gravity (g) on earth’s surface is given as g = `"GM"/"R"^2`. The value of g depends on the mass M of the earth and the radius R of the earth.
- As we go inside the earth, our distance from the centre of the earth decreases and no longer remains equal to the radius of the earth (R).
- Along with the distance, the part of the earth which contributes towards the gravitational force felt also decreases, decreasing the value of (M).
- Due to the combined result of a change in R and M, the value of g decreases as we go deep inside the earth.
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